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Topic: Power jack for arduino prototyping (Read 152 times) previous topic - next topic

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I found this tutorial for building your own arduino on a breadboard.

http://arduino.cc/en/Main/Standalone

I'm planning to do that on a PCB and also  power the the processor with 12V DC.
The thing is, where should I connect the power jack ?

I would connect it to either pin 7 or 20 but not sure what the difference is between Vcc and AVcc

And also how can I reach to 5V output ? Is it also introduced through voltage divider on the arduino board ?


LarryD

#1
Jul 10, 2014, 12:52 am Last Edit: Jul 10, 2014, 12:55 am by LarryD Reason: 1
Quote
power the the processor with 12V DC.

+12 anode of 1N4007 cathode to 7805 regulator input, 7805 regulator output is +5V.
Of course you will power the 7805 with 12V and feed the o/p of the 7805 to the processor VCC(7) and AVcc(20) .
Aref(21) to 100nf to ground.
VCC(7) to 100nF to ground.
AVcc(20) to 100nF to ground.
The way you have it in your schematic isn't the same as how you have it wired up!

polymorph

5V and -only- 5V connects to both Vcc and AVcc. Do NOT connect 12V to those pins. It should go to ground and the input of the 7805, seen here:



That page is flawed - there should be several 0.1uF bypass caps across both power rails, one right at AVcc, and on ARef.
Steve Greenfield AE7HD
Nick Gammon on multitasking Arduinos:
http://gammon.com.au/blink
http://gammon.com.au/serial
http://gammon.com.au/interrupts

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